Search (168 results, page 1 of 9)

  • × language_ss:"e"
  • × theme_ss:"Automatisches Klassifizieren"
  1. Hotho, A.; Bloehdorn, S.: Data Mining 2004 : Text classification by boosting weak learners based on terms and concepts (2004) 0.05
    0.053947702 = product of:
      0.107895404 = sum of:
        0.07624002 = product of:
          0.22872004 = sum of:
            0.22872004 = weight(_text_:3a in 562) [ClassicSimilarity], result of:
              0.22872004 = score(doc=562,freq=2.0), product of:
                0.4069621 = queryWeight, product of:
                  8.478011 = idf(docFreq=24, maxDocs=44218)
                  0.04800207 = queryNorm
                0.56201804 = fieldWeight in 562, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  8.478011 = idf(docFreq=24, maxDocs=44218)
                  0.046875 = fieldNorm(doc=562)
          0.33333334 = coord(1/3)
        0.031655382 = product of:
          0.04748307 = sum of:
            0.008461362 = weight(_text_:a in 562) [ClassicSimilarity], result of:
              0.008461362 = score(doc=562,freq=8.0), product of:
                0.055348642 = queryWeight, product of:
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.04800207 = queryNorm
                0.15287387 = fieldWeight in 562, product of:
                  2.828427 = tf(freq=8.0), with freq of:
                    8.0 = termFreq=8.0
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.046875 = fieldNorm(doc=562)
            0.039021708 = weight(_text_:22 in 562) [ClassicSimilarity], result of:
              0.039021708 = score(doc=562,freq=2.0), product of:
                0.16809508 = queryWeight, product of:
                  3.5018296 = idf(docFreq=3622, maxDocs=44218)
                  0.04800207 = queryNorm
                0.23214069 = fieldWeight in 562, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  3.5018296 = idf(docFreq=3622, maxDocs=44218)
                  0.046875 = fieldNorm(doc=562)
          0.6666667 = coord(2/3)
      0.5 = coord(2/4)
    
    Abstract
    Document representations for text classification are typically based on the classical Bag-Of-Words paradigm. This approach comes with deficiencies that motivate the integration of features on a higher semantic level than single words. In this paper we propose an enhancement of the classical document representation through concepts extracted from background knowledge. Boosting is used for actual classification. Experimental evaluations on two well known text corpora support our approach through consistent improvement of the results.
    Content
    Vgl.: http://www.google.de/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&ved=0CEAQFjAA&url=http%3A%2F%2Fciteseerx.ist.psu.edu%2Fviewdoc%2Fdownload%3Fdoi%3D10.1.1.91.4940%26rep%3Drep1%26type%3Dpdf&ei=dOXrUMeIDYHDtQahsIGACg&usg=AFQjCNHFWVh6gNPvnOrOS9R3rkrXCNVD-A&sig2=5I2F5evRfMnsttSgFF9g7Q&bvm=bv.1357316858,d.Yms.
    Date
    8. 1.2013 10:22:32
    Type
    a
  2. Shen, D.; Chen, Z.; Yang, Q.; Zeng, H.J.; Zhang, B.; Lu, Y.; Ma, W.Y.: Web page classification through summarization (2004) 0.03
    0.02635539 = product of:
      0.10542156 = sum of:
        0.10542156 = product of:
          0.15813233 = sum of:
            0.007051134 = weight(_text_:a in 4132) [ClassicSimilarity], result of:
              0.007051134 = score(doc=4132,freq=2.0), product of:
                0.055348642 = queryWeight, product of:
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.04800207 = queryNorm
                0.12739488 = fieldWeight in 4132, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.078125 = fieldNorm(doc=4132)
            0.15108119 = weight(_text_:z in 4132) [ClassicSimilarity], result of:
              0.15108119 = score(doc=4132,freq=2.0), product of:
                0.2562021 = queryWeight, product of:
                  5.337313 = idf(docFreq=577, maxDocs=44218)
                  0.04800207 = queryNorm
                0.58969533 = fieldWeight in 4132, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  5.337313 = idf(docFreq=577, maxDocs=44218)
                  0.078125 = fieldNorm(doc=4132)
          0.6666667 = coord(2/3)
      0.25 = coord(1/4)
    
    Type
    a
  3. Koch, T.; Vizine-Goetz, D.: DDC and knowledge organization in the digital library : Research and development. Demonstration pages (1999) 0.02
    0.016721193 = product of:
      0.033442385 = sum of:
        0.03203216 = weight(_text_:von in 942) [ClassicSimilarity], result of:
          0.03203216 = score(doc=942,freq=4.0), product of:
            0.12806706 = queryWeight, product of:
              2.6679487 = idf(docFreq=8340, maxDocs=44218)
              0.04800207 = queryNorm
            0.2501202 = fieldWeight in 942, product of:
              2.0 = tf(freq=4.0), with freq of:
                4.0 = termFreq=4.0
              2.6679487 = idf(docFreq=8340, maxDocs=44218)
              0.046875 = fieldNorm(doc=942)
        0.001410227 = product of:
          0.004230681 = sum of:
            0.004230681 = weight(_text_:a in 942) [ClassicSimilarity], result of:
              0.004230681 = score(doc=942,freq=2.0), product of:
                0.055348642 = queryWeight, product of:
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.04800207 = queryNorm
                0.07643694 = fieldWeight in 942, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.046875 = fieldNorm(doc=942)
          0.33333334 = coord(1/3)
      0.5 = coord(2/4)
    
    Abstract
    Der Workshop gibt einen Einblick in die aktuelle Forschung und Entwicklung zur Wissensorganisation in digitalen Bibliotheken. Diane Vizine-Goetz vom OCLC Office of Research in Dublin, Ohio, stellt die Forschungsprojekte von OCLC zur Anpassung und Weiterentwicklung der Dewey Decimal Classification als Wissensorganisationsinstrument fuer grosse digitale Dokumentensammlungen vor. Traugott Koch, NetLab, Universität Lund in Schweden, demonstriert die Ansätze und Lösungen des EU-Projekts DESIRE zum Einsatz von intellektueller und vor allem automatischer Klassifikation in Fachinformationsdiensten im Internet.
    Content
    1. Increased Importance of Knowledge Organization in Internet Services - 2. Quality Subject Service and the role of classification - 3. Developing the DDC into a knowledge organization instrument for the digital library. OCLC site - 4. DESIRE's Barefoot Solutions of Automatic Classification - 5. Advanced Classification Solutions in DESIRE and CORC - 6. Future directions of research and development - 7. General references
  4. Aphinyanaphongs, Y.; Fu, L.D.; Li, Z.; Peskin, E.R.; Efstathiadis, E.; Aliferis, C.F.; Statnikov, A.: ¬A comprehensive empirical comparison of modern supervised classification and feature selection methods for text categorization (2014) 0.02
    0.016684802 = product of:
      0.06673921 = sum of:
        0.06673921 = product of:
          0.10010881 = sum of:
            0.00946009 = weight(_text_:a in 1496) [ClassicSimilarity], result of:
              0.00946009 = score(doc=1496,freq=10.0), product of:
                0.055348642 = queryWeight, product of:
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.04800207 = queryNorm
                0.1709182 = fieldWeight in 1496, product of:
                  3.1622777 = tf(freq=10.0), with freq of:
                    10.0 = termFreq=10.0
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.046875 = fieldNorm(doc=1496)
            0.09064872 = weight(_text_:z in 1496) [ClassicSimilarity], result of:
              0.09064872 = score(doc=1496,freq=2.0), product of:
                0.2562021 = queryWeight, product of:
                  5.337313 = idf(docFreq=577, maxDocs=44218)
                  0.04800207 = queryNorm
                0.35381722 = fieldWeight in 1496, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  5.337313 = idf(docFreq=577, maxDocs=44218)
                  0.046875 = fieldNorm(doc=1496)
          0.6666667 = coord(2/3)
      0.25 = coord(1/4)
    
    Abstract
    An important aspect to performing text categorization is selecting appropriate supervised classification and feature selection methods. A comprehensive benchmark is needed to inform best practices in this broad application field. Previous benchmarks have evaluated performance for a few supervised classification and feature selection methods and limited ways to optimize them. The present work updates prior benchmarks by increasing the number of classifiers and feature selection methods order of magnitude, including adding recently developed, state-of-the-art methods. Specifically, this study used 229 text categorization data sets/tasks, and evaluated 28 classification methods (both well-established and proprietary/commercial) and 19 feature selection methods according to 4 classification performance metrics. We report several key findings that will be helpful in establishing best methodological practices for text categorization.
    Type
    a
  5. Subramanian, S.; Shafer, K.E.: Clustering (2001) 0.01
    0.014417464 = product of:
      0.057669856 = sum of:
        0.057669856 = product of:
          0.08650478 = sum of:
            0.008461362 = weight(_text_:a in 1046) [ClassicSimilarity], result of:
              0.008461362 = score(doc=1046,freq=2.0), product of:
                0.055348642 = queryWeight, product of:
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.04800207 = queryNorm
                0.15287387 = fieldWeight in 1046, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.09375 = fieldNorm(doc=1046)
            0.078043416 = weight(_text_:22 in 1046) [ClassicSimilarity], result of:
              0.078043416 = score(doc=1046,freq=2.0), product of:
                0.16809508 = queryWeight, product of:
                  3.5018296 = idf(docFreq=3622, maxDocs=44218)
                  0.04800207 = queryNorm
                0.46428138 = fieldWeight in 1046, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  3.5018296 = idf(docFreq=3622, maxDocs=44218)
                  0.09375 = fieldNorm(doc=1046)
          0.6666667 = coord(2/3)
      0.25 = coord(1/4)
    
    Date
    5. 5.2003 14:17:22
    Type
    a
  6. Ma, Z.; Sun, A.; Cong, G.: On predicting the popularity of newly emerging hashtags in Twitter (2013) 0.01
    0.014029406 = product of:
      0.056117624 = sum of:
        0.056117624 = product of:
          0.084176436 = sum of:
            0.00863584 = weight(_text_:a in 967) [ClassicSimilarity], result of:
              0.00863584 = score(doc=967,freq=12.0), product of:
                0.055348642 = queryWeight, product of:
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.04800207 = queryNorm
                0.15602624 = fieldWeight in 967, product of:
                  3.4641016 = tf(freq=12.0), with freq of:
                    12.0 = termFreq=12.0
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.0390625 = fieldNorm(doc=967)
            0.075540595 = weight(_text_:z in 967) [ClassicSimilarity], result of:
              0.075540595 = score(doc=967,freq=2.0), product of:
                0.2562021 = queryWeight, product of:
                  5.337313 = idf(docFreq=577, maxDocs=44218)
                  0.04800207 = queryNorm
                0.29484767 = fieldWeight in 967, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  5.337313 = idf(docFreq=577, maxDocs=44218)
                  0.0390625 = fieldNorm(doc=967)
          0.6666667 = coord(2/3)
      0.25 = coord(1/4)
    
    Abstract
    Because of Twitter's popularity and the viral nature of information dissemination on Twitter, predicting which Twitter topics will become popular in the near future becomes a task of considerable economic importance. Many Twitter topics are annotated by hashtags. In this article, we propose methods to predict the popularity of new hashtags on Twitter by formulating the problem as a classification task. We use five standard classification models (i.e., Naïve bayes, k-nearest neighbors, decision trees, support vector machines, and logistic regression) for prediction. The main challenge is the identification of effective features for describing new hashtags. We extract 7 content features from a hashtag string and the collection of tweets containing the hashtag and 11 contextual features from the social graph formed by users who have adopted the hashtag. We conducted experiments on a Twitter data set consisting of 31 million tweets from 2 million Singapore-based users. The experimental results show that the standard classifiers using the extracted features significantly outperform the baseline methods that do not use these features. Among the five classifiers, the logistic regression model performs the best in terms of the Micro-F1 measure. We also observe that contextual features are more effective than content features.
    Type
    a
  7. Chung, Y.M.; Lee, J.Y.: ¬A corpus-based approach to comparative evaluation of statistical term association measures (2001) 0.01
    0.013904001 = product of:
      0.055616003 = sum of:
        0.055616003 = product of:
          0.083424 = sum of:
            0.007883408 = weight(_text_:a in 5769) [ClassicSimilarity], result of:
              0.007883408 = score(doc=5769,freq=10.0), product of:
                0.055348642 = queryWeight, product of:
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.04800207 = queryNorm
                0.14243183 = fieldWeight in 5769, product of:
                  3.1622777 = tf(freq=10.0), with freq of:
                    10.0 = termFreq=10.0
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.0390625 = fieldNorm(doc=5769)
            0.075540595 = weight(_text_:z in 5769) [ClassicSimilarity], result of:
              0.075540595 = score(doc=5769,freq=2.0), product of:
                0.2562021 = queryWeight, product of:
                  5.337313 = idf(docFreq=577, maxDocs=44218)
                  0.04800207 = queryNorm
                0.29484767 = fieldWeight in 5769, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  5.337313 = idf(docFreq=577, maxDocs=44218)
                  0.0390625 = fieldNorm(doc=5769)
          0.6666667 = coord(2/3)
      0.25 = coord(1/4)
    
    Abstract
    Statistical association measures have been widely applied in information retrieval research, usually employing a clustering of documents or terms on the basis of their relationships. Applications of the association measures for term clustering include automatic thesaurus construction and query expansion. This research evaluates the similarity of six association measures by comparing the relationship and behavior they demonstrate in various analyses of a test corpus. Analysis techniques include comparisons of highly ranked term pairs and term clusters, analyses of the correlation among the association measures using Pearson's correlation coefficient and MDS mapping, and an analysis of the impact of a term frequency on the association values by means of z-score. The major findings of the study are as follows: First, the most similar association measures are mutual information and Yule's coefficient of colligation Y, whereas cosine and Jaccard coefficients, as well as X**2 statistic and likelihood ratio, demonstrate quite similar behavior for terms with high frequency. Second, among all the measures, the X**2 statistic is the least affected by the frequency of terms. Third, although cosine and Jaccard coefficients tend to emphasize high frequency terms, mutual information and Yule's Y seem to overestimate rare terms
    Type
    a
  8. HaCohen-Kerner, Y. et al.: Classification using various machine learning methods and combinations of key-phrases and visual features (2016) 0.01
    0.012014553 = product of:
      0.04805821 = sum of:
        0.04805821 = product of:
          0.07208732 = sum of:
            0.007051134 = weight(_text_:a in 2748) [ClassicSimilarity], result of:
              0.007051134 = score(doc=2748,freq=2.0), product of:
                0.055348642 = queryWeight, product of:
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.04800207 = queryNorm
                0.12739488 = fieldWeight in 2748, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.078125 = fieldNorm(doc=2748)
            0.065036185 = weight(_text_:22 in 2748) [ClassicSimilarity], result of:
              0.065036185 = score(doc=2748,freq=2.0), product of:
                0.16809508 = queryWeight, product of:
                  3.5018296 = idf(docFreq=3622, maxDocs=44218)
                  0.04800207 = queryNorm
                0.38690117 = fieldWeight in 2748, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  3.5018296 = idf(docFreq=3622, maxDocs=44218)
                  0.078125 = fieldNorm(doc=2748)
          0.6666667 = coord(2/3)
      0.25 = coord(1/4)
    
    Date
    1. 2.2016 18:25:22
    Type
    a
  9. Zhang, X: Rough set theory based automatic text categorization (2005) 0.01
    0.010677386 = product of:
      0.042709544 = sum of:
        0.042709544 = weight(_text_:von in 2822) [ClassicSimilarity], result of:
          0.042709544 = score(doc=2822,freq=4.0), product of:
            0.12806706 = queryWeight, product of:
              2.6679487 = idf(docFreq=8340, maxDocs=44218)
              0.04800207 = queryNorm
            0.3334936 = fieldWeight in 2822, product of:
              2.0 = tf(freq=4.0), with freq of:
                4.0 = termFreq=4.0
              2.6679487 = idf(docFreq=8340, maxDocs=44218)
              0.0625 = fieldNorm(doc=2822)
      0.25 = coord(1/4)
    
    Abstract
    Der Forschungsbericht "Rough Set Theory Based Automatic Text Categorization and the Handling of Semantic Heterogeneity" von Xueying Zhang ist in Buchform auf Englisch erschienen. Zhang hat in ihrer Arbeit ein Verfahren basierend auf der Rough Set Theory entwickelt, das Beziehungen zwischen Schlagwörtern verschiedener Vokabulare herstellt. Sie war von 2003 bis 2005 Mitarbeiterin des IZ und ist seit Oktober 2005 Associate Professor an der Nanjing University of Science and Technology.
  10. Yoon, Y.; Lee, C.; Lee, G.G.: ¬An effective procedure for constructing a hierarchical text classification system (2006) 0.01
    0.010055452 = product of:
      0.040221807 = sum of:
        0.040221807 = product of:
          0.060332708 = sum of:
            0.014807383 = weight(_text_:a in 5273) [ClassicSimilarity], result of:
              0.014807383 = score(doc=5273,freq=18.0), product of:
                0.055348642 = queryWeight, product of:
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.04800207 = queryNorm
                0.26752928 = fieldWeight in 5273, product of:
                  4.2426405 = tf(freq=18.0), with freq of:
                    18.0 = termFreq=18.0
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.0546875 = fieldNorm(doc=5273)
            0.045525327 = weight(_text_:22 in 5273) [ClassicSimilarity], result of:
              0.045525327 = score(doc=5273,freq=2.0), product of:
                0.16809508 = queryWeight, product of:
                  3.5018296 = idf(docFreq=3622, maxDocs=44218)
                  0.04800207 = queryNorm
                0.2708308 = fieldWeight in 5273, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  3.5018296 = idf(docFreq=3622, maxDocs=44218)
                  0.0546875 = fieldNorm(doc=5273)
          0.6666667 = coord(2/3)
      0.25 = coord(1/4)
    
    Abstract
    In text categorization tasks, classification on some class hierarchies has better results than in cases without the hierarchy. Currently, because a large number of documents are divided into several subgroups in a hierarchy, we can appropriately use a hierarchical classification method. However, we have no systematic method to build a hierarchical classification system that performs well with large collections of practical data. In this article, we introduce a new evaluation scheme for internal node classifiers, which can be used effectively to develop a hierarchical classification system. We also show that our method for constructing the hierarchical classification system is very effective, especially for the task of constructing classifiers applied to hierarchy tree with a lot of levels.
    Date
    22. 7.2006 16:24:52
    Type
    a
  11. Jenkins, C.: Automatic classification of Web resources using Java and Dewey Decimal Classification (1998) 0.01
    0.009427017 = product of:
      0.037708066 = sum of:
        0.037708066 = product of:
          0.0565621 = sum of:
            0.011036771 = weight(_text_:a in 1673) [ClassicSimilarity], result of:
              0.011036771 = score(doc=1673,freq=10.0), product of:
                0.055348642 = queryWeight, product of:
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.04800207 = queryNorm
                0.19940455 = fieldWeight in 1673, product of:
                  3.1622777 = tf(freq=10.0), with freq of:
                    10.0 = termFreq=10.0
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.0546875 = fieldNorm(doc=1673)
            0.045525327 = weight(_text_:22 in 1673) [ClassicSimilarity], result of:
              0.045525327 = score(doc=1673,freq=2.0), product of:
                0.16809508 = queryWeight, product of:
                  3.5018296 = idf(docFreq=3622, maxDocs=44218)
                  0.04800207 = queryNorm
                0.2708308 = fieldWeight in 1673, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  3.5018296 = idf(docFreq=3622, maxDocs=44218)
                  0.0546875 = fieldNorm(doc=1673)
          0.6666667 = coord(2/3)
      0.25 = coord(1/4)
    
    Abstract
    The Wolverhampton Web Library (WWLib) is a WWW search engine that provides access to UK based information. The experimental version developed in 1995, was a success but highlighted the need for a much higher degree of automation. An interesting feature of the experimental WWLib was that it organised information according to DDC. Discusses the advantages of classification and describes the automatic classifier that is being developed in Java as part of the new, fully automated WWLib
    Date
    1. 8.1996 22:08:06
    Footnote
    Contribution to a special issue devoted to the Proceedings of the 7th International World Wide Web Conference, held 14-18 April 1998, Brisbane, Australia; vgl. auch: http://www7.scu.edu.au/programme/posters/1846/com1846.htm.
    Type
    a
  12. Yi, K.: Automatic text classification using library classification schemes : trends, issues and challenges (2007) 0.01
    0.009427017 = product of:
      0.037708066 = sum of:
        0.037708066 = product of:
          0.0565621 = sum of:
            0.011036771 = weight(_text_:a in 2560) [ClassicSimilarity], result of:
              0.011036771 = score(doc=2560,freq=10.0), product of:
                0.055348642 = queryWeight, product of:
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.04800207 = queryNorm
                0.19940455 = fieldWeight in 2560, product of:
                  3.1622777 = tf(freq=10.0), with freq of:
                    10.0 = termFreq=10.0
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.0546875 = fieldNorm(doc=2560)
            0.045525327 = weight(_text_:22 in 2560) [ClassicSimilarity], result of:
              0.045525327 = score(doc=2560,freq=2.0), product of:
                0.16809508 = queryWeight, product of:
                  3.5018296 = idf(docFreq=3622, maxDocs=44218)
                  0.04800207 = queryNorm
                0.2708308 = fieldWeight in 2560, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  3.5018296 = idf(docFreq=3622, maxDocs=44218)
                  0.0546875 = fieldNorm(doc=2560)
          0.6666667 = coord(2/3)
      0.25 = coord(1/4)
    
    Abstract
    The proliferation of digital resources and their integration into a traditional library setting has created a pressing need for an automated tool that organizes textual information based on library classification schemes. Automated text classification is a research field of developing tools, methods, and models to automate text classification. This article describes the current popular approach for text classification and major text classification projects and applications that are based on library classification schemes. Related issues and challenges are discussed, and a number of considerations for the challenges are examined.
    Date
    22. 9.2008 18:31:54
    Type
    a
  13. Egbert, J.; Biber, D.; Davies, M.: Developing a bottom-up, user-based method of web register classification (2015) 0.01
    0.008842215 = product of:
      0.03536886 = sum of:
        0.03536886 = product of:
          0.05305329 = sum of:
            0.014031581 = weight(_text_:a in 2158) [ClassicSimilarity], result of:
              0.014031581 = score(doc=2158,freq=22.0), product of:
                0.055348642 = queryWeight, product of:
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.04800207 = queryNorm
                0.25351265 = fieldWeight in 2158, product of:
                  4.690416 = tf(freq=22.0), with freq of:
                    22.0 = termFreq=22.0
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.046875 = fieldNorm(doc=2158)
            0.039021708 = weight(_text_:22 in 2158) [ClassicSimilarity], result of:
              0.039021708 = score(doc=2158,freq=2.0), product of:
                0.16809508 = queryWeight, product of:
                  3.5018296 = idf(docFreq=3622, maxDocs=44218)
                  0.04800207 = queryNorm
                0.23214069 = fieldWeight in 2158, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  3.5018296 = idf(docFreq=3622, maxDocs=44218)
                  0.046875 = fieldNorm(doc=2158)
          0.6666667 = coord(2/3)
      0.25 = coord(1/4)
    
    Abstract
    This paper introduces a project to develop a reliable, cost-effective method for classifying Internet texts into register categories, and apply that approach to the analysis of a large corpus of web documents. To date, the project has proceeded in 2 key phases. First, we developed a bottom-up method for web register classification, asking end users of the web to utilize a decision-tree survey to code relevant situational characteristics of web documents, resulting in a bottom-up identification of register and subregister categories. We present details regarding the development and testing of this method through a series of 10 pilot studies. Then, in the second phase of our project we applied this procedure to a corpus of 53,000 web documents. An analysis of the results demonstrates the effectiveness of these methods for web register classification and provides a preliminary description of the types and distribution of registers on the web.
    Date
    4. 8.2015 19:22:04
    Type
    a
  14. Dubin, D.: Dimensions and discriminability (1998) 0.01
    0.008750932 = product of:
      0.03500373 = sum of:
        0.03500373 = product of:
          0.052505594 = sum of:
            0.0069802674 = weight(_text_:a in 2338) [ClassicSimilarity], result of:
              0.0069802674 = score(doc=2338,freq=4.0), product of:
                0.055348642 = queryWeight, product of:
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.04800207 = queryNorm
                0.12611452 = fieldWeight in 2338, product of:
                  2.0 = tf(freq=4.0), with freq of:
                    4.0 = termFreq=4.0
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.0546875 = fieldNorm(doc=2338)
            0.045525327 = weight(_text_:22 in 2338) [ClassicSimilarity], result of:
              0.045525327 = score(doc=2338,freq=2.0), product of:
                0.16809508 = queryWeight, product of:
                  3.5018296 = idf(docFreq=3622, maxDocs=44218)
                  0.04800207 = queryNorm
                0.2708308 = fieldWeight in 2338, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  3.5018296 = idf(docFreq=3622, maxDocs=44218)
                  0.0546875 = fieldNorm(doc=2338)
          0.6666667 = coord(2/3)
      0.25 = coord(1/4)
    
    Abstract
    Visualization interfaces can improve subject access by highlighting the inclusion of document representation components in similarity and discrimination relationships. Within a set of retrieved documents, what kinds of groupings can index terms and subject headings make explicit? The role of controlled vocabulary in classifying search output is examined
    Date
    22. 9.1997 19:16:05
    Type
    a
  15. Liu, R.-L.: Context recognition for hierarchical text classification (2009) 0.01
    0.008369173 = product of:
      0.03347669 = sum of:
        0.03347669 = product of:
          0.050215036 = sum of:
            0.0111933295 = weight(_text_:a in 2760) [ClassicSimilarity], result of:
              0.0111933295 = score(doc=2760,freq=14.0), product of:
                0.055348642 = queryWeight, product of:
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.04800207 = queryNorm
                0.20223314 = fieldWeight in 2760, product of:
                  3.7416575 = tf(freq=14.0), with freq of:
                    14.0 = termFreq=14.0
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.046875 = fieldNorm(doc=2760)
            0.039021708 = weight(_text_:22 in 2760) [ClassicSimilarity], result of:
              0.039021708 = score(doc=2760,freq=2.0), product of:
                0.16809508 = queryWeight, product of:
                  3.5018296 = idf(docFreq=3622, maxDocs=44218)
                  0.04800207 = queryNorm
                0.23214069 = fieldWeight in 2760, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  3.5018296 = idf(docFreq=3622, maxDocs=44218)
                  0.046875 = fieldNorm(doc=2760)
          0.6666667 = coord(2/3)
      0.25 = coord(1/4)
    
    Abstract
    Information is often organized as a text hierarchy. A hierarchical text-classification system is thus essential for the management, sharing, and dissemination of information. It aims to automatically classify each incoming document into zero, one, or several categories in the text hierarchy. In this paper, we present a technique called CRHTC (context recognition for hierarchical text classification) that performs hierarchical text classification by recognizing the context of discussion (COD) of each category. A category's COD is governed by its ancestor categories, whose contents indicate contextual backgrounds of the category. A document may be classified into a category only if its content matches the category's COD. CRHTC does not require any trials to manually set parameters, and hence is more portable and easier to implement than other methods. It is empirically evaluated under various conditions. The results show that CRHTC achieves both better and more stable performance than several hierarchical and nonhierarchical text-classification methodologies.
    Date
    22. 3.2009 19:11:54
    Type
    a
  16. Zhu, W.Z.; Allen, R.B.: Document clustering using the LSI subspace signature model (2013) 0.01
    0.0077249105 = product of:
      0.030899642 = sum of:
        0.030899642 = product of:
          0.046349462 = sum of:
            0.007327754 = weight(_text_:a in 690) [ClassicSimilarity], result of:
              0.007327754 = score(doc=690,freq=6.0), product of:
                0.055348642 = queryWeight, product of:
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.04800207 = queryNorm
                0.13239266 = fieldWeight in 690, product of:
                  2.4494898 = tf(freq=6.0), with freq of:
                    6.0 = termFreq=6.0
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.046875 = fieldNorm(doc=690)
            0.039021708 = weight(_text_:22 in 690) [ClassicSimilarity], result of:
              0.039021708 = score(doc=690,freq=2.0), product of:
                0.16809508 = queryWeight, product of:
                  3.5018296 = idf(docFreq=3622, maxDocs=44218)
                  0.04800207 = queryNorm
                0.23214069 = fieldWeight in 690, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  3.5018296 = idf(docFreq=3622, maxDocs=44218)
                  0.046875 = fieldNorm(doc=690)
          0.6666667 = coord(2/3)
      0.25 = coord(1/4)
    
    Abstract
    We describe the latent semantic indexing subspace signature model (LSISSM) for semantic content representation of unstructured text. Grounded on singular value decomposition, the model represents terms and documents by the distribution signatures of their statistical contribution across the top-ranking latent concept dimensions. LSISSM matches term signatures with document signatures according to their mapping coherence between latent semantic indexing (LSI) term subspace and LSI document subspace. LSISSM does feature reduction and finds a low-rank approximation of scalable and sparse term-document matrices. Experiments demonstrate that this approach significantly improves the performance of major clustering algorithms such as standard K-means and self-organizing maps compared with the vector space model and the traditional LSI model. The unique contribution ranking mechanism in LSISSM also improves the initialization of standard K-means compared with random seeding procedure, which sometimes causes low efficiency and effectiveness of clustering. A two-stage initialization strategy based on LSISSM significantly reduces the running time of standard K-means procedures.
    Date
    23. 3.2013 13:22:36
    Type
    a
  17. Liu, R.-L.: ¬A passage extractor for classification of disease aspect information (2013) 0.01
    0.0074551697 = product of:
      0.029820679 = sum of:
        0.029820679 = product of:
          0.044731017 = sum of:
            0.012212924 = weight(_text_:a in 1107) [ClassicSimilarity], result of:
              0.012212924 = score(doc=1107,freq=24.0), product of:
                0.055348642 = queryWeight, product of:
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.04800207 = queryNorm
                0.22065444 = fieldWeight in 1107, product of:
                  4.8989797 = tf(freq=24.0), with freq of:
                    24.0 = termFreq=24.0
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.0390625 = fieldNorm(doc=1107)
            0.032518093 = weight(_text_:22 in 1107) [ClassicSimilarity], result of:
              0.032518093 = score(doc=1107,freq=2.0), product of:
                0.16809508 = queryWeight, product of:
                  3.5018296 = idf(docFreq=3622, maxDocs=44218)
                  0.04800207 = queryNorm
                0.19345059 = fieldWeight in 1107, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  3.5018296 = idf(docFreq=3622, maxDocs=44218)
                  0.0390625 = fieldNorm(doc=1107)
          0.6666667 = coord(2/3)
      0.25 = coord(1/4)
    
    Abstract
    Retrieval of disease information is often based on several key aspects such as etiology, diagnosis, treatment, prevention, and symptoms of diseases. Automatic identification of disease aspect information is thus essential. In this article, I model the aspect identification problem as a text classification (TC) problem in which a disease aspect corresponds to a category. The disease aspect classification problem poses two challenges to classifiers: (a) a medical text often contains information about multiple aspects of a disease and hence produces noise for the classifiers and (b) text classifiers often cannot extract the textual parts (i.e., passages) about the categories of interest. I thus develop a technique, PETC (Passage Extractor for Text Classification), that extracts passages (from medical texts) for the underlying text classifiers to classify. Case studies on thousands of Chinese and English medical texts show that PETC enhances a support vector machine (SVM) classifier in classifying disease aspect information. PETC also performs better than three state-of-the-art classifier enhancement techniques, including two passage extraction techniques for text classifiers and a technique that employs term proximity information to enhance text classifiers. The contribution is of significance to evidence-based medicine, health education, and healthcare decision support. PETC can be used in those application domains in which a text to be classified may have several parts about different categories.
    Date
    28.10.2013 19:22:57
    Type
    a
  18. Mengle, S.; Goharian, N.: Passage detection using text classification (2009) 0.01
    0.00708165 = product of:
      0.0283266 = sum of:
        0.0283266 = product of:
          0.0424899 = sum of:
            0.0099718105 = weight(_text_:a in 2765) [ClassicSimilarity], result of:
              0.0099718105 = score(doc=2765,freq=16.0), product of:
                0.055348642 = queryWeight, product of:
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.04800207 = queryNorm
                0.18016359 = fieldWeight in 2765, product of:
                  4.0 = tf(freq=16.0), with freq of:
                    16.0 = termFreq=16.0
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.0390625 = fieldNorm(doc=2765)
            0.032518093 = weight(_text_:22 in 2765) [ClassicSimilarity], result of:
              0.032518093 = score(doc=2765,freq=2.0), product of:
                0.16809508 = queryWeight, product of:
                  3.5018296 = idf(docFreq=3622, maxDocs=44218)
                  0.04800207 = queryNorm
                0.19345059 = fieldWeight in 2765, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  3.5018296 = idf(docFreq=3622, maxDocs=44218)
                  0.0390625 = fieldNorm(doc=2765)
          0.6666667 = coord(2/3)
      0.25 = coord(1/4)
    
    Abstract
    Passages can be hidden within a text to circumvent their disallowed transfer. Such release of compartmentalized information is of concern to all corporate and governmental organizations. Passage retrieval is well studied; we posit, however, that passage detection is not. Passage retrieval is the determination of the degree of relevance of blocks of text, namely passages, comprising a document. Rather than determining the relevance of a document in its entirety, passage retrieval determines the relevance of the individual passages. As such, modified traditional information-retrieval techniques compare terms found in user queries with the individual passages to determine a similarity score for passages of interest. In passage detection, passages are classified into predetermined categories. More often than not, passage detection techniques are deployed to detect hidden paragraphs in documents. That is, to hide information, documents are injected with hidden text into passages. Rather than matching query terms against passages to determine their relevance, using text-mining techniques, the passages are classified. Those documents with hidden passages are defined as infected. Thus, simply stated, passage retrieval is the search for passages relevant to a user query, while passage detection is the classification of passages. That is, in passage detection, passages are labeled with one or more categories from a set of predetermined categories. We present a keyword-based dynamic passage approach (KDP) and demonstrate that KDP outperforms statistically significantly (99% confidence) the other document-splitting approaches by 12% to 18% in the passage detection and passage category-prediction tasks. Furthermore, we evaluate the effects of the feature selection, passage length, ambiguous passages, and finally training-data category distribution on passage-detection accuracy.
    Date
    22. 3.2009 19:14:43
    Type
    a
  19. Khoo, C.S.G.; Ng, K.; Ou, S.: ¬An exploratory study of human clustering of Web pages (2003) 0.01
    0.0051499405 = product of:
      0.020599762 = sum of:
        0.020599762 = product of:
          0.030899642 = sum of:
            0.004885169 = weight(_text_:a in 2741) [ClassicSimilarity], result of:
              0.004885169 = score(doc=2741,freq=6.0), product of:
                0.055348642 = queryWeight, product of:
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.04800207 = queryNorm
                0.088261776 = fieldWeight in 2741, product of:
                  2.4494898 = tf(freq=6.0), with freq of:
                    6.0 = termFreq=6.0
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.03125 = fieldNorm(doc=2741)
            0.026014473 = weight(_text_:22 in 2741) [ClassicSimilarity], result of:
              0.026014473 = score(doc=2741,freq=2.0), product of:
                0.16809508 = queryWeight, product of:
                  3.5018296 = idf(docFreq=3622, maxDocs=44218)
                  0.04800207 = queryNorm
                0.15476047 = fieldWeight in 2741, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  3.5018296 = idf(docFreq=3622, maxDocs=44218)
                  0.03125 = fieldNorm(doc=2741)
          0.6666667 = coord(2/3)
      0.25 = coord(1/4)
    
    Abstract
    This study seeks to find out how human beings cluster Web pages naturally. Twenty Web pages retrieved by the Northem Light search engine for each of 10 queries were sorted by 3 subjects into categories that were natural or meaningful to them. lt was found that different subjects clustered the same set of Web pages quite differently and created different categories. The average inter-subject similarity of the clusters created was a low 0.27. Subjects created an average of 5.4 clusters for each sorting. The categories constructed can be divided into 10 types. About 1/3 of the categories created were topical. Another 20% of the categories relate to the degree of relevance or usefulness. The rest of the categories were subject-independent categories such as format, purpose, authoritativeness and direction to other sources. The authors plan to develop automatic methods for categorizing Web pages using the common categories created by the subjects. lt is hoped that the techniques developed can be used by Web search engines to automatically organize Web pages retrieved into categories that are natural to users. 1. Introduction The World Wide Web is an increasingly important source of information for people globally because of its ease of access, the ease of publishing, its ability to transcend geographic and national boundaries, its flexibility and heterogeneity and its dynamic nature. However, Web users also find it increasingly difficult to locate relevant and useful information in this vast information storehouse. Web search engines, despite their scope and power, appear to be quite ineffective. They retrieve too many pages, and though they attempt to rank retrieved pages in order of probable relevance, often the relevant documents do not appear in the top-ranked 10 or 20 documents displayed. Several studies have found that users do not know how to use the advanced features of Web search engines, and do not know how to formulate and re-formulate queries. Users also typically exert minimal effort in performing, evaluating and refining their searches, and are unwilling to scan more than 10 or 20 items retrieved (Jansen, Spink, Bateman & Saracevic, 1998). This suggests that the conventional ranked-list display of search results does not satisfy user requirements, and that better ways of presenting and summarizing search results have to be developed. One promising approach is to group retrieved pages into clusters or categories to allow users to navigate immediately to the "promising" clusters where the most useful Web pages are likely to be located. This approach has been adopted by a number of search engines (notably Northem Light) and search agents.
    Date
    12. 9.2004 9:56:22
    Type
    a
  20. Automatic classification research at OCLC (2002) 0.00
    0.0037937774 = product of:
      0.01517511 = sum of:
        0.01517511 = product of:
          0.045525327 = sum of:
            0.045525327 = weight(_text_:22 in 1563) [ClassicSimilarity], result of:
              0.045525327 = score(doc=1563,freq=2.0), product of:
                0.16809508 = queryWeight, product of:
                  3.5018296 = idf(docFreq=3622, maxDocs=44218)
                  0.04800207 = queryNorm
                0.2708308 = fieldWeight in 1563, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  3.5018296 = idf(docFreq=3622, maxDocs=44218)
                  0.0546875 = fieldNorm(doc=1563)
          0.33333334 = coord(1/3)
      0.25 = coord(1/4)
    
    Date
    5. 5.2003 9:22:09

Years

Types

  • a 150
  • el 21
  • m 1
  • r 1
  • s 1
  • More… Less…